I rather think your engineer might find that the prop dome was built that way purely to contain the pitch change mechanism.
In those design days, the hand-start inertia system was available for when the electrical motor was inoperative.
B377 - inertia starters were in common use (in the UK at least) until the mid eighties. Then all overhauled engines came with direct drive starters. Sometimes a block of wood and a lump hammer was needed to wake them up and the pax reaction was as Capot describes.
